Diagnosis and treatment of tick infestation and tick-borne diseases with cutaneous manifestations

Dermatological aspects of ticks in Australia: An update

Ticks are ectoparasites that cause dermatologic reactions directly by their bites and indirectly as vectors of bacterial, protozoal and viral diseases. Consequences vary from minor local reactions to significant systemic sequelae and are therefore of clinical relevance to dermatologists. In this article, Australian ticks of medical importance are reviewed through the lens of dermatology.

Approach to the Patient with a Skin and Soft Tissue Infection

The diagnosis of a skin and soft tissue infection (SSTI) requires careful attention to a patient's history, physical examination, and diagnostic test results. We review for many bacterial, viral, fungal, and parasitic pathogens that cause SSTIs the clues for reaching a diagnosis, including reported past medical history, hobbies and behaviors, travel, insect bites, exposure to other people and to animals, environmental exposures to water, soil, or sand, as well as the anatomic site of skin lesions, their morphology on examination, and their evolution over time. Laboratory and radiographic tests are discussed that may be used to confirm a specific diagnosis.

Idiopathic, Infectious and Reactive Lesions of the Ear and Temporal Bone

A number of infectious, inflammatory and idiopathic lesions develop within otologic tissues that may share similar clinical and/or microscopic features. This review first provides a working classification for otitis externa, and then otitis media and includes two recently described entities, eosinophilic otitis media and otitis media with ANCA-associated vasculitis. Next, the microscopic findings of a spectrum of otopathologic conditions are described, including post-inflammatory conditions such as tympanosclerosis and aural polyps, an overview of animate aural foreign body as well as iatrogenic aural foreign body reactions. Finally, a review of fungal disease affecting the ear with a brief synopsis of Candida auris, a recently described and virulent organism, is presented.

Animal, Microbial, and Fungal Borne Skin Pathology in the Mountain Wilderness: A Review

Mountains are home to numerous organisms known to cause skin disease. Bites, stings, poisons, chemicals, toxins, trauma, and infections all contribute to this end. Numerous plants, animals, fungi, bacteria, viruses, and protozoa are responsible. This paper aims to review skin illness and injury sustained from organisms in the mountains of North America. Other factors such as increased ultraviolet radiation, temperature extremes, and decreasing atmospheric pressure along with human physiologic parameters, which contribute to disease severity, will also be discussed. After reading this review, one should feel more comfortable identifying potentially harmful organisms, as well as diagnosing, treating, and preventing organism-inflicted skin pathology sustained in the high country.

Variation in Tularemia Clinical Manifestations-Arkansas, 2009-2013

BACKGROUND

Francisella tularensis, although naturally occurring in Arkansas, is also a Tier 1 select agent and potential bioterrorism threat. As such, tularemia is nationally notifiable and mandatorily reported to the Arkansas Department of Health. We examined demographic and clinical characteristics among reported cases and outcomes to improve understanding of the epidemiology of tularemia in Arkansas.

METHODS

Surveillance records on all tularemia cases investigated during 2009-2013 were reviewed.

RESULTS

The analytic dataset was assembled from 284 tularemia reports, yielding 138 probable and confirmed tularemia cases during 2009-2013. Arthropod bite was identified in 77% of cases. Of 7 recognized tularemia manifestations, the typhoidal form was reported in 47% of cases, approximately double the proportion of the more classic manifestation, lymphadenopathy. Overall, 41% of patients were hospitalized; 3% died. The typhoidal form appeared to be more severe, accounting for the majority of sepsis and meningitis cases, hospitalizations, and deaths. Among patients with available antibiotic data, 88% received doxycycline and 12% received gentamicin.

CONCLUSIONS

Contrary to expectation, lymphadenopathy was not the most common manifestation observed in our registry. Instead, our patients were more likely to report only generalized typhoidal symptoms. Using lymphadenopathy as a primary symptom to initiate tularemia testing may be an insensitive diagnostic strategy and result in unrecognized cases. In endemic areas such as Arkansas, suspicion of tularemia should be high, especially during tick season. Outreach to clinicians describing the full range of presenting symptoms may help address misperceptions about tularemia.

Indian Tick Typhus Presenting as Purpura Fulminans with Review on Rickettsial Infections

Rickettsial diseases are some of the most covert reemerging infections of the present times. They are generally incapacitating and notoriously difficult to diagnose; untreated cases can have fatality rates as high as 30%-35%, but when diagnosed properly, they are often easily treated but lack of definite diagnostic tools and the hazards of handling these microorganisms aggravate the difficulties of diagnosis and treatment.

Diversity and distribution of tick species (Acari: Ixodidae) associated with human otoacariasis and socio-ecological risk factors of tick infestations in Sri Lanka

Tick infestation in humans is a major public health concern. The diversity and distribution of tick species associated with human otoacariasis was studied in five districts: Anuradhapura, Kandy, Kurunegala, Nuwara Eliya and Ratnapura in the main agro-climatic zones of Sri Lanka. Ticks from patients attending the ear, nose and throat clinics of the General Hospitals were collected during a 3 year period. In total 426 ticks were collected. Most human otoacariasis cases were reported from Kandy (33.8 %) and the fewest from Nuwara Eliya (8.2 %). Of the five tick species identified, nymphs of Dermacentor auratus constituted 90.6 % of the collection. Rhipicephalus sanguineus, Hyalomma isaaci, Haemaphysalis bispinosa and Otobius megnini were found rarely infesting humans possibly as an accidental host; H. bispinosa and O. megnini in the human ear canal were first time records in Sri Lanka. Females and children under 10 years were identified as risk groups of human otoacariasis. Subsequently, a field study was carried out to determine socio-ecological risk factors of human tick infestations in the five districts. Based on hospital data, eight villages with high prevalence of otoacariasis were selected from each district. A total 40 villages were visited and 1674 household members were interviewed. Involvement in outdoor activities, presence of wild animals around the house, location of the house in close proximity to a forest and occupation were identified as major risk factors.

Arthropod-Borne Diseases: The Camper's Uninvited Guests

Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.

Small risk of developing symptomatic tick-borne diseases following a tick bite in The Netherlands

Background

In The Netherlands, the incidence of Lyme borreliosis is on the rise. Besides its causative agent, Borrelia burgdorferi s.l., other potential pathogens like Rickettsia, Babesia and Ehrlichia species are present in Ixodes ricinus ticks. The risk of disease associated with these microorganisms after tick-bites remains, however, largely unclear. A prospective study was performed to investigate how many persons with tick-bites develop localized or systemic symptoms and whether these are associated with tick-borne microorganisms.

Results

In total, 297 Ixodes ricinus ticks were collected from 246 study participants who consulted a general practitioner on the island of Ameland for tick bites. Ticks were subjected to PCR to detect DNA of Borrelia burgdorferi s.l., Rickettsia spp., Babesia spp. or Ehrlichia/Anaplasma spp.. Sixteen percent of the collected ticks were positive for Borrelia burgdorferi s.l., 19% for Rickettsia spp., 12% for Ehrlichia/Anaplasma spp. and 10% for Babesia spp.. At least six months after the tick bite, study participants were interviewed on symptoms by means of a standard questionnaire. 14 out of 193 participants (8.3%) reported reddening at the bite site and 6 participants (4.1%) reported systemic symptoms. No association between symptoms and tick-borne microorganisms was found. Attachment duration ≥24 h was positively associated with reddening at the bite site and systemic symptoms. Using logistic regression techniques, reddening was positively correlated with presence of Borrelia afzelii, and having 'any symptoms' was positively associated with attachment duration.

Conclusion

The risk of contracting acute Lyme borreliosis, rickettsiosis, babesiosis or ehrlichiosis from a single tick bite was <1% in this study population.